1. Field of the Invention
The present invention relates generally to a mobile communication system, and in particular, to a method for providing an interactive data service between a base station and a mobile station.
2. Description of the Related Art
In the next generation mobile communication, a matter of grave concern is high-speed data transmission. For example, 3GPP2 (3rd Generation Partnership Project 2) makes a study of a mobile communication system for high-speed data transmission, such as 1xEV-DV (1x Evolution Data and Voice). In a 3GPP2 mobile communication system, a broadcast service is taken into consideration for efficient resource management and various service media.
The broadcast service is a service in which a mobile station receives high-speed forward data from a base station without transmission of reverse feedback information to the base station. That is, a base station provides a broadcast service by simultaneously transmitting data to mobile stations at high speed. According to 3GPP2, a supplemental channel, which is a dedicated channel, is used for a broadcast service. The supplemental channel is a dedicated channel for which a common long code mask is used instead of a dedicated long code mask.
The 3GPP2 considers factors for preventing excessive consumption of cell capacity in a mobile communication system for high-speed data transmission. In order to prevent the excessive consumption of cell capacity, 3GPP2 proposes an autonomous handoff operation and an outer coding operation, in which a base station does not require feedback information from a mobile station. Although a dedicated channel is used in those operations, higher performance and lower power consumption are guaranteed as compared with when a common channel is used. When a broadcast service is provided using a common channel, excessive consumption of cell capacity is inevitable in order to guarantee the same performance even up to the cell boundary. In addition, 3GPP2 proposes a general concept of preventing a waste of reverse cell capacity by suppressing the use of a dedicated reverse channel for transmitting power control information and feedback information from a mobile station to a base station, thereby accommodating a great number of mobile stations within a cell.
As described above, no reverse channel is used for a broadcast service in a mobile communication system for high-speed data transmission proposed in 3GPP2. That is, because there are no means for delivering information from a mobile station to a base station, an interactive broadcast service cannot be provided.